The dude in the newspaper ad is buff. The dude has guns. The dude has washboard abs, thick shoulders, a massive chest.

And the dude is, well, old.

He's 67.

From the neck up, he looks like your typical Social Security recipient. But thanks to something called Cenegenics, from the neck down he's got the body of a 27-year-old linebacker.

When you were a kid, it might have been Charles Atlas in comic books, taunting you about being a skinny weakling. If you thought reaching middle age would give you a break from such pressure, think again.

Now it's a man named Jeffry Life serving as the poster boy - or poster grandfather - saying you too can have that hot bod, even if you might need reading glasses to check out the ad he adorns.

FOUNTAIN OF YOUTH - With baby boomers getting up there, the fight against aging is rocking and rolling. CNS Illustration by Jacie Landeros.

With baby boomers getting up there, the fight against time is rocking 'n' rolling. Forget about easing into a rocking chair at retirement. Settle into a Bowflex.

Older people are exercising more. Eating better. And some - like Life - are amping up their testosterone levels and trying other hormone replenishments, despite warnings that such treatments are unproven and could be dangerous.

Life is a medical doctor who works for Cenegenics, a company developed in the late 1990s to sell these controversial treatments - in addition to diet and exercise - to turn back the clock.

It works, Life swears. Ten years ago, he had a gut, man boobs, flabby arms. Today, he could be a Calvin Klein underwear model.

"And I think I could look even better," said Life, who works at Cenegenics' Las Vegas headquarters.

Using hormones to help old guys look good in Speedos is pretty controversial stuff in the medical community.

The American Medical Association has warned doctors that it is illegal to dispense human-growth hormone for anti-aging purposes. Some experts warn that HGH therapy may cause considerable harm, such as raising the risk of cancer and diabetes.

Cenegenics gives human-growth hormone to 7 percent of its patients - those showing true deficits, it says. And regardless of the red flags being waved, Cenegenics and other companies are finding customers among middle-aged people who want to go toe-to-toe against aging.

Sixty-year-old Sylvester Stallone - who sells a line of nutritional supplements, including one that stimulates testosterone levels - recently made another Rocky movie. And, yo, Rocky is not using a walker. He actually looks good.

He's muscled. He's got a full head of hair. Something definitely seems skewed.

In the not-too-distant past, people got old and they got soft. It was the way of things. Even many once-elite athletes packed on pounds after retirement and lost a bit of their hair. Golf courses - not barbells - were calling.

Now, women are having babies at 60.

And men as old as the universe are looking to be Mr. Universe.

The people at Cenegenics say there's no reason for us to get flabby just because we get old.

Michael Resnick, another doctor at Cenegenics, says there's nothing spooky about it. Men lose hormones as they age. Some lose too much, Resnick said. That can be rectified.

"Everybody understands that there's nothing good about getting old," said Resnick, 59. "Ask any old person."

An obstetrician and gynecologist by training, Resnick once practiced in San Diego and did health reports on TV. The father of two children, ages 4 and 7, he said he wouldn't have the energy to keep up with them if it weren't for Cenegenics.

The system is not cheap. The initial evaluation costs $2,495 and the monthly charge for vitamins, supplements and hormone therapy can run $300 to $400. The average age of the 13,000 clients is 45.

Not everyone thinks such "age management" systems are the true fountain of youth. Some people believe diet and exercise are all that's necessary to stay vibrant past middle age and that messing with hormones and testosterone is a waste of money.

But watch out.

Say that and one of these graying Cenegenics gramps might just kick sand in your face. Talk about embarrassing.